For many years, terrorism rhetoric has been used as a blunt weapon by governments seeking to stifle dissent and escape international scrutiny. This new approach by the US is a key step in recasting the term and clarifying what exactly constitutes international terrorism.

Since 9/11, the "terrorist" label has become rampant worldwide. Examples include the Chinese government using it to stifle dissent in Tibet, the Russian government employing it in regard to Chechnya, and the Chilean government invoking an archaic terrorism law to target leaders of the country's largest indigenous group.

In many instances, the use has become synonymous with a get-out-of-accountability-free card. International human rights law places significant restraints on government conduct. But where there is an emergency situation – such as a terrorist threat – governments are able to ignore many international human rights standards.

And what makes the linguistic quagmire that much more difficult is that the terrorist label also has been directed at governments. In 2007, the Bush administration designated Iran's Revolutionary Guard – the country's 125,000-strong elite military branch – a terrorist organization. And in recent months, Israel repeatedly was labeled a terrorist state for its incursion into Gaza.

Can national governments, Osama bin Laden, and the Dalai Lama all be guilty of terrorism? Pragmatically, the answer is clear.

For the term to be useful, it must have definitive meaning. But, as the concept currently is defined in international law, it is not at all clear. Despite numerous attempts to reach consensus, there are 12 different definitions in various international treaties. Failure to reach consensus, combined with the US "war on terror," has left the term ripe for unchecked use.

Of course, even if there were a consensus definition, "terrorist" would continue to be used in indiscriminate and self-serving ways.

But having prompted its recent misuse, the responsibility falls on the US to lead an effort to rein in the term's use and to work toward definitional clarity. The new US approach to Afghanistan could be a great start to recasting the term.

In March, President Obama said the return of the Taliban to leadership also would mean the return to force of Al Qaeda terrorists. But he also expressed a desire to reach out to moderate elements of the Taliban. This nod – that a group that previously had been categorically associated with supporting terrorism can have both moderate and extremist elements – is an important step.

And there are other promising signs, including Secretary Clinton's recent call to the international community to support efforts by Afghanistan to separate Al Qaeda and Taliban extremists from those who are willing to abandon violence and reintegrate into society.

In recognizing nuance among such groups, the US lends a critical hand to undoing damage done by the "war on terror." The US must continue to recognize that terrorism is a heinous act, but one that involves specific conduct. The indiscriminate use of "terrorist" not only has been devastating to groups to whom the label has been unfairly attached, but it also has damaged efforts to isolate those who deserve international condemnation as terrorists.